Optical sight

ABSTRACT

An optical sight is provided and may include a housing, an optical element supported by the housing, and a reticle. An illumination system may selectively display the reticle on the optical element and may include a switch supplying the optical element with light from one of a first light source and a second light source to generate the reticle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/570,377, filed on Sep. 30, 2009, which claims the benefit of U.S.Provisional Application No. 61/102,222, filed on Oct. 2, 2008. Theentire disclosures of the above applications are incorporated herein byreference.

FIELD

The present disclosure relates to sighting systems and more particularlyto an optical sighting system.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

Firearms conventionally incorporate a sight to aid in aligning atrajectory of the firearm with a target. In one configuration, the sightincludes an upwardly extending arm fixed relative to a barrel of afirearm, whereby a user of the firearm may properly align an end of thebarrel with a target by aligning the upwardly extending arm with thetarget.

In addition to use of a fixed, upwardly extending arm, conventionalfirearm sights may also incorporate an optical element that displays anilluminated reticle for use in aligning a barrel of a firearm with atarget. One such prior-art sight is disclosed in U.S. Pat. No.6,327,806. The foregoing sight incorporates an optical element, whichreceives light from a light emitting diode (LED) and displays a reticleon a lens for use by a user in aligning a barrel of a firearm with atarget. Such a sight incorporating a lens and an illuminated reticle isgenerally an improvement over a firearm incorporating a fixed, upwardlyextending arm, as the illuminated reticle of the optical sight may beviewed from numerous angles from a rear portion of the firearm and doesnot have to be exactly aligned with an eye of the user. Allowing thereticle to be viewed from numerous angles from an area generally behindthe firearm allows the user to be positioned somewhat offset from alongitudinal axis of the firearm while still maintaining a barrel of thefirearm trained on a target.

While the foregoing optical sight is an improvement over a fixed,upwardly extending arm disposed proximate to an end of a firearm,conventional optical sights typically include an optical lens having agenerally convex upper surface, which is easily fractured if dropped.While conventional optical sights typically include a housing having aportion extending over the convex upper surface, the housing typicallyincludes a similar convex shape and, as such, transmits a force appliedat an outer surface thereof directly to an outer surface of the lens,thereby causing the lens to fracture. Once the lens of the optical sightis fractured, the sight may not be used and, therefore, reduces theoverall effectiveness of the firearm.

In addition to the likelihood of fracture, conventional optical sightssuffer from the disadvantage of including an LED, which requires a powersource to illuminate a reticle. While such LEDs adequately illuminate areticle, the power source supplying power to the LED is not infinite.Because the power source supplying power to the LED is not infinite,care must be taken to routinely check the life of the power source toensure that the reticle is consistently displayed. While recharging orreplacing the power source of a conventional sight is relatively simple,such tasks become difficult in a military or law enforcement operationwhere time is of the essence and reliability on equipment is key. Havinga power source expire during a law enforcement or military operationreduces the overall effectiveness of the firearm on which the opticalsight is mounted and, as a result, reduces the effectiveness of the lawenforcement agent or soldier.

Based on the foregoing, an optical sight incorporating multiple lightsources, such as, for example, an LED, a fiber optic, and a tritiumlamp, that can accommodate various ambient-light conditions is desirablein the industry. Incorporating multiple light sources into an opticalsight provides flexibility in illuminating a reticle, as each source ora combination of sources can be chosen based on the particularambient-light conditions.

In one configuration, light from the fiber optic and tritium lamp may becombined to illuminate a reticle. In another configuration, light fromthe LED may additionally or alternatively be used should the suppliedlight from the fiber optic and/or tritium lamp be insufficient. Furtheryet, light from any one of the sources may be used independently of theother sources. In any of the foregoing configurations, providing anoptical sight with multiple light sources allows the optical sight to beused in virtually any ambient-light condition and provides the user witha reliable and useful sight.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

An optical sight is provided and may include a housing, an opticalelement supported by the housing, and a reticle. An illumination systemmay selectively display the reticle on the optical element and mayinclude a switch supplying the optical element with light from one of afirst light source and a second light source to generate the reticle.

In another configuration, an optical sight may include a housing, anoptical element supported by the housing, and a reticle. An illuminationsystem may selectively display the reticle on the optical element andmay include a beam splitter combining light from a first light sourceand a second light source to generate the reticle. The beam splitter mayinclude a mask formed on a surface of the beam splitter and may define ashape of the reticle.

In another configuration, an optical sight may include a housing, anoptical element supported by the housing, and a reticle. An illuminationsystem may include a light source for selectively displaying the reticleon the optical element and a photo detector operable to detect ambientlight conditions. The photo detector may be exposed to ambient lightconditions via the optical element.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a perspective view of a firearm incorporating an optical sightin accordance with the principles of the present disclosure;

FIG. 2 is a perspective view of the firearm of FIG. 1 showing a rearportion of the optical sight;

FIG. 3 is a cross sectional view of the optical sight of FIG. 1 takenalong line A-A;

FIG. 4 is a cross sectional view of the optical sight of FIG. 1 takenalong line B-B;

FIG. 5 is an exploded view of the optical sight of FIG. 1;

FIG. 6 is a perspective view of a firearm incorporating another opticalsight in accordance with the principles of the present disclosure;

FIG. 7 is a perspective view of the firearm of FIG. 6 showing a rearportion of the optical sight;

FIG. 8 is a cross sectional view of the optical sight of FIG. 6 takenalong line A-A;

FIG. 9 is a cross sectional view of the optical sight of FIG. 6 takenalong line B-B;

FIG. 10 is an exploded view of the optical sight of FIG. 6;

FIG. 11 is an exploded view of an optical sight in accordance with theprinciples of the present disclosure;

FIG. 12A is a schematic representation of a beam splitter for use withan optical sight in accordance with the principles of the presentdisclosure;

FIG. 12B is a schematic representation of a beam splitter incorporatinga mask and reticle configuration for use with an optical sight inaccordance with the principles of the present disclosure;

FIG. 12C is a schematic representation of a beam splitter incorporatinga mask and reticle configuration for use with an optical sight inaccordance with the principles of the present disclosure;

FIG. 12D is a schematic representation of a beam splitter incorporatinga mask and reticle configuration for use with an optical sight inaccordance with the principles of the present disclosure;

FIG. 13 is a perspective view of a switch for use with an optical sightin accordance with the principles of the present disclosure;

FIG. 14 is a cross sectional view of the switch of FIG. 12; and

FIG. 15 is a perspective view of a base for use in supporting an opticalsight in accordance with the principles of the present disclosure on afirearm.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

With reference to the figures, an optical sight 10 is provided and mayinclude a housing 12, an adjustment assembly 14, an illuminationassembly 16, and an optical element 18. Each of the adjustment assembly14, illumination assembly 16, and optical element 18 may be supported byand attached to the housing 12 such that the housing 12 supports theadjustment assembly 14, illumination assembly 16 and optical element 18relative to a firearm 20. When the housing 12 is mounted to the firearm20, the illumination assembly 16 may cooperate with the optical element18 to display a reticle 22 on the optical element 18 to facilitatealignment of a trajectory of the firearm 20 with a target (not shown).The adjustment assembly 14 may interact with the illumination assembly16 to move the illumination assembly 16 relative to the housing 12 toadjust a position of the reticle 22 relative to the optical element 18.While the optical sight 10 may be used with various firearms, such as,for example, a bow or rocket launcher, the optical sight 10 will bedescribed hereinafter and shown in the drawings as being associated witha barrel 24 of a firearm 20.

The housing 12 may include a main body 26 and an upwardly extendingportion 28 extending generally from the main body 26 and including alongitudinal axis substantially ninety degrees to a longitudinal axis ofthe main body 26. The main body 26 may include a first aperture 30formed through a top surface 32 and a second aperture 34 formed througha side surface 36. The top surface 32 may include a series ofgraduations 38 generally surrounding a perimeter of the first aperture30, while the side surface 36 may likewise include a series ofgraduations 40 that generally surround an outer perimeter of the secondaperture 34. The graduations 38, 40 may cooperate with the adjustmentassembly 14 to position the illumination assembly 16 relative to theoptical element 18, as will be described further below.

The main body 26 may also include a recess 42 having a series of steps44. The recess 42 and steps 44 cooperate to allow the illuminationassembly 16 to direct light generally from the main body 26 of thehousing 12 toward the optical element 18. The recess 42 may be formedgenerally between a pair of attachment apertures 46 that are disposedgenerally within the recess 42 and between the main body 26 and theupwardly extending portion 28. The attachment apertures 46 selectivelyreceive a pair of fasteners 48 that removably attach the housing 12 tothe firearm 20.

In one configuration, the fasteners 48 include a threaded shank 50, ahead portion 52, and a taper 54 extending generally between the threadedshank 50 and the head portion 52. The head portion 52 may include ahexagonal configuration 56 as well as a longitudinal slot 58 thatcooperate with an external tool (not shown) to rotate the fasteners 48relative to the main body 26 of the housing 12 and selectively attachthe housing 12 to the firearm 20. The hexagonal configuration 56 may beused with a tool having a mating male portion while the longitudinalslot 58 may be used with a tool having a substantially flat male end.While the head portion 52 is described as including a hexagonalconfiguration 56 and a longitudinal slot 58 that receive tools having arespective mating configuration, the longitudinal slot 58 may be sizedsuch that any flat surface can be used to rotate the fasteners 48relative to the housing 12. For example, the longitudinal slots 58 mayinclude a sufficient width and thickness to allow a spent shell casingto be used to rotate the fasteners relative to the housing 12.

The main body 26 may also include at least one drain opening 60 formedtherethrough and in communication with the recess 42. The drain openings60 may be positioned relative to the recess 42 such that the drainopenings 60 are in fluid communication with a lower-most step 44, asshown in FIG. 3. Positioning the drain opening 60 proximate to thelowest step 44 allows water that collects generally within the recess 42and on any of the steps 44 to flow down to the lowest step 44 and beexpelled from the housing 12 via the drain opening 60. Removing waterfrom the housing 12 at the recess 42 improves the ability of theillumination assembly 16 in directing light toward the optical element18 and prevents water from entering the housing 12.

With particular reference to FIGS. 4 and 5, the upwardly extendingportion 28 is shown and may include a pair of posts 62, an opening 64,and a cross member 66 extending generally over the opening 64 andbetween the posts 62. The posts 62 may be formed at a substantiallyninety degree angle relative to the main body 26 and may extend apredetermined distance above the opening 64. The opening 64 may includea generally D-shape to accommodate the optical element 18 therein. Thecross member 66 provides the opening 64 with the D-shape and may includea bottom surface 68 opposing the opening 64 having a convex shape and atop surface 70 having a concave shape. The concave shape of the topsurface 70 allows the top surface 70 to extend from the main body 26 ashorter distance than each of the posts 62. In other words, the posts 62extend from the main body 26 a greater distance than does the topsurface 70 of the cross member 66. As such, should the housing 12 bedropped such that the upwardly extending portion 28 contacts a hardsurface, the force associated with the upwardly extending portion 28contacting the hard surface is received by a distal end of each post 62and is transmitted to the main body 26 rather than being received at thegenerally convex bottom surface 68 of the cross member 66. Transmittingforces generally away from the opening 64 and through the posts 62toward the main body 26 protects the optical element 18 disposed withinthe opening 64 and prevents the optical element 18 from being fracturedshould the housing 12 be dropped or suffer an impact event.

The main body 26 and upwardly extending portion 28 may be integrallyformed and may be formed of a one-piece metal construction. Forming themain body 26 and the upwardly extending portion 28 as a one-piece metalbody strengthens the housing 12 and allows the housing 12 to withstandforces applied to either the main body 26 or the upwardly extendingportion 28. In particular, forces applied to the posts 62 of theupwardly extending portion 28 are directly transferred from the upwardlyextending portion 28 to the main body 26. Such forces are thereforediverted away from the optical element 18, thereby protecting theoptical element 18, as described above. Forming the main body of aone-piece metal construction enhances the ability of the posts 62 intransmitting forces from a distal end of each post 62 to the main body26.

The adjustment assembly 14 may be supported by the housing 12 and mayadjust a position of the illumination assembly 16 relative to thehousing 12 to adjust a position of the reticle 22 relative to theoptical element 18. The adjustment assembly 14 may include aheight-adjustment mechanism 72 that adjusts an UP/DOWN position of thereticle 22 and a windage-adjustment mechanism 74 that adjusts aleft-right position of the reticle 22 relative to the optical element18.

The height-adjustment mechanism 72 may include an adjustment screw 76,an adjuster block 78, and a biasing member 80. The adjustment screw 76may be rotatably received within the first aperture 30 of the main body26 and may be rotated relative to the graduations 38. The adjustmentscrew 76 may include a threaded body 82, a head 84, and a taper 86extending generally between the threaded body 82 and the head 84. Thehead 84 may include a slot 88 to allow a tool (not shown) to be insertedinto the head 84 to rotate the head 84 relative to the housing 12. Aseal 90 may be disposed between the taper 86 of the adjustment screw 76and an inner surface of the first aperture 30 to prevent debris fromentering the main body 26. In one configuration, the seal 90 is anO-ring seal that is received generally around the taper 86 of theadjustment screw 76.

The taper 86 may also include a series of detents 77 in communicationwith a detent pin 79. The detent pin 79 may be slidably supported withina bore 81 of the housing 12, whereby the bore 81 is in communicationwith the first aperture 30 of the main body 26. A biasing member 83 suchas, for example, a coil spring, may be disposed within the bore 81 andmy impart a biasing force on the detent pin 79 to urge the detent pin 79into the first aperture 30. When the screw 76 is inserted into the firstaperture 30, a distal end of the detent pin 79 may engage the detents 77formed in the taper 86 of the screw 76. When the screw 76 is rotatedrelative to the housing 12, the detent pin 79 is moved into an out ofengagement with adjacent detents 77 and makes an audible noise to allowthe user to know exactly how much the screw 76 has been rotated relativeto the housing 12.

The detent pin 79 may include a tapered portion 85 terminating at apoint 87 at a distal end of the detent pin 79. Likewise, each detent 77may include a tapered surface 89, whereby the tapered portion 85 of thedetent pin 79 engages the tapered surface 89 of a respective detent 77to allow the screw 76 to be rotated in two directions relative to thehousing 12 and to facilitate movement of the point 87 of the detent pin79 into and out of each detent 77 when the screw 76 is rotated relativeto the housing 12. The angle of the tapered portion 85 of the detent pin79 and/or that of the tapered surface 89 of the detents 77 can beadjusted to either increase or decrease the force required to rotate thescrew 76 relative to the housing 12 and/or to adjust the audible noisecreated when the screw 76 is rotated relative to the housing 12.Furthermore, the spring constant of the biasing member 83 may also beadjusted to both adjust the force required to rotate the screw 76relative to the housing 12 as well as to adjust the audible noisecreated when the detent pin 79 moves from one detent 77 to an adjacentdetent 77 caused by rotation of the screw relative to the housing 12.

A clip 92 may be received around a portion of the adjustment screw 76generally at a location where the threaded body 82 meets the taper 86.The clip may secure the adjustment screw 76 to the main body 26 suchthat the adjustment screw 76 is prevented from being removed from themain body 26 while concurrently allowing the adjustment screw 76 to berotated relative to the main body 26. In one configuration, the clip 92is an E-clip that includes an opening that may be snapped intoengagement with the adjustment screw 76 once the adjustment screw 76 isinserted into the first aperture 30 of the main body 26. Once the clip92 is snapped into engagement with the adjustment screw 76, theadjustment screw 76 may be rotated relative to the main body 26 but maynot be withdrawn from the first aperture 30 until the clip 92 isremoved.

The adjuster block 78 may interact with the illumination assembly 16 tomove the illumination assembly 16 up/down relative to the housing 12.The adjuster block 78 may include a threaded bore 94, a slot 96 in fluidcommunication with the threaded bore 94 and extending along the lengthof the threaded bore 94, and a projection 98. The adjustment screw 76may be threadably received within the threaded bore 94 of the adjusterblock 78 such that when the adjustment screw 76 is rotated relative tothe housing 12, the adjuster block 78 is moved along an axissubstantially perpendicular to the top surface 32 of the main body 26.Because the projection 98 is in engagement with the illuminationassembly 16 and is fixed for movement with the adjuster block 78,movement of the projection 98 similarly causes the illumination assembly16 to move relative to the housing 12.

The slot 96 allows the adjuster block 78 to compress generally aroundthe threaded body 82 of the adjustment screw 76. Allowing the adjusterblock 78 to compress and closely engage the threaded body 82 of theadjustment screw 76 maintains tight engagement between the adjusterblock 78 and the adjustment screw 76.

The biasing member 80 may be disposed between the adjuster block 78 andthe illumination assembly 16 and may bias the adjuster block 78generally along the longitudinal axis of the housing 12 to account forany tolerances in the housing 12, illumination assembly 16, screw 76,and/or adjuster block 78. In one configuration, the biasing member 80 isan O-ring and applies a force on the adjuster block 78 to maintain theadjustment assembly 14 in a desired position in a directionsubstantially parallel to the longitudinal axis of the housing 12 (i.e.,substantially parallel to a line of sight). Allowing the O-ring toimpart a force on the adjuster block 78 maintains tight engagementbetween the adjustment screw 76 and the adjuster block 78 and thereforeallows for precise manipulation and movement of the adjuster block 78relative to the housing 12 while concurrently maintaining a desiredposition of the adjustment assembly 14 in the direction substantiallyparallel to the line of sight.

The position of the illumination assembly 16 relative to the housing 12may be determined based on the position of the adjustment screw 76relative to the housing 12. For example, the graduations 38 formed onthe top surface 32 of the main body 26 may help in determining therelative position of the adjustment screw 76 relative to the main body26 and, thus, the position of the illumination assembly 16 relative tothe main body 26.

The graduations 38 may be permanently attached to the top surface 32 ofthe housing 12 either via paint and/or laser etching. As such, thegraduations 38 maintain the same fixed position relative to the topsurface 32 and allow a user to know precisely how much the adjustmentscrew 76 has moved relative to the housing 12. Furthermore, eachgraduation 38 may be positioned relative to each detent 77 such thateach audible noise or “click” corresponds to movement of the screw 76one graduation 38.

Once adjustment of the adjustment screw 76 is completed, the biasingmember 80, in conjunction with the adjuster block 78, preventsunintended rotation of the adjustment screw 76 due to vibration and thelike relative to the housing 12 and, as such, maintains the adjustedposition of the adjustment screw 76.

A biasing member 91 may be used on conjunction with biasing member 80 tofurther maintain a position of the screw 76 relative to the housing 12.The biasing member 91 may apply a force on the adjuster block 78 and maybe positioned between the adjuster block 78 and the housing 12 to exerta force on the adjuster block 78. In another configuration, the biasingmember 91 may be positioned between a portion of the illuminationassembly 16 and the housing 12 to indirectly impart a force on theadjuster block 78. In either configuration, the biasing member 91 may bea coil spring and may be positioned and held relative to the adjusterblock 78 by a post 93 received within a bore 95 of either the adjusterblock 78 or a component of the illumination assembly 16 (one or both ofelements 130, 138 for example). Imparting a force on the adjuster block78 likewise applies a force on the screw 76 and therefore resistsrelative movement between the screw 76 and the adjuster block 78.

With particular reference to FIGS. 4 and 5, the windage-adjustmentmechanism 74 may include an adjustment screw 100, a first adjuster block102, a second adjuster block 104, and a biasing member 106. Theadjustment screw 100 may be of a similar construction to that of theadjustment screw 76 and may include a threaded body 108, a head 110, ataper 112 extending generally between the threaded body 108 and the head110, and a slot formed in the head 110. As with the adjustment screw 76,the adjustment screw 100 may be rotated relative to the housing 12 butis not permitted to move along a longitudinal axis extendingsubstantially perpendicular to the side surface 36 of the main body 26.A clip 116 may be disposed generally at a junction of the threaded body108 and the taper 112 to permit rotational movement of the adjustmentscrew 100 relative to the main body 26 while concurrently preventingwithdrawal of the adjustment screw 100 from the main body 26. The clip116 may be received generally around the adjustment screw 100 once theadjustment screw 100 is inserted into the main body 26.

A seal 118 may be positioned generally between the head 110 of theadjustment screw 100 to prevent debris from entering the housing 12. Theseal may engage the taper 112 of the adjustment screw 100 and maysimilarly engage a surface proximate to the second aperture 34 of themain body 26. In one configuration, the seal 118 is an O-ring andgenerally surrounds the taper 112 of the adjustment screw 100.

The taper 112 may include a series of detents 101 in communication witha detent pin 103. The detent pin 103 may be slidably supported within abore 105 of the housing 12, whereby the bore 105 is in communicationwith the second aperture 34 of the main body 26. A biasing member 107such as, for example, a coil spring, may be disposed within the bore 105and my impart a biasing force on the detent pin 103 to urge the detentpin 103 into the second aperture 34. When the screw 100 is inserted intothe second aperture 34, a distal end of the detent pin 103 may engagethe detents 101 formed in the taper 112 of the screw 100. When the screw100 is rotated relative to the housing 12, the detent pin 103 is movedinto an out of engagement with adjacent detents 101 and makes an audiblenoise to allow the user to know exactly how much the screw 100 has beenrotated relative to the housing 12.

The detent pin 103 may include a tapered portion 109 terminating at apoint 111 at a distal end of the detent pin 103. Likewise, each detent101 may include a tapered surface 113, whereby the tapered portion 109of the detent pin 103 engages the tapered surface 113 of a respectivedetent 101 to allow the screw 100 to be rotated in two directionsrelative to the housing 12 and to facilitate movement of the point 111of the detent pin 103 into and out of each detent 101 when the screw 100is rotated relative to the housing 12. The angle of the tapered portion109 of the detent pin 103 and/or that of the tapered surface 113 of thedetents 101 can be adjusted to either increase or decrease the forcerequired to rotate the screw 100 relative to the housing 12 and/or toadjust the audible noise created when the screw 100 is rotated relativeto the housing 12. Furthermore, the spring constant of the biasingmember 107 may also be adjusted to both adjust the force required torotate the screw 100 relative to the housing 12 as well as to adjust theaudible noise created when the detent pin 103 moves from one detent 101to an adjacent detent 101 caused by rotation of the screw relative tothe housing 12.

The first adjuster block 102 may include a threaded bore 120, a slot 122extending generally along a length of and in fluid communication withthe threaded bore 120, and a recess 124 formed in a body of the firstadjuster block 102 in a direction substantially perpendicular to theslot 122. As with the adjuster block 78, the threaded body 108 of theadjustment screw 100 may be threadably received therein such thatrotation of the adjustment screw 100 relative to the main body 26 causesthe first adjuster block 102 to translate relative to the housing 12along the longitudinal axis extending substantially perpendicular to theside surface 36. The slot 122 allows the adjuster block 102 to compressgenerally around the threaded body 108 of the adjustment screw 100 tomaintain a tight engagement between the threaded bore 120 and thethreaded body 108 of the adjustment screw 100. The recess 124 mayreceive a portion of the illumination assembly 16 such that when thefirst adjuster block 102 is translated relative to the housing 12, theillumination assembly 16 is similarly translated relative to the housing12. Translating the illumination assembly 16 relative to the housingsimilarly causes the reticle 22 to be translated relative to the opticalelement 18 to adjust the position of the reticle 22 relative to theoptical element 18. Adjusting the left/right position of the reticle 22relative to the optical element 18 adjusts the “windage” of the opticalsight 10.

The second adjuster block 104 is similar to the first adjuster block 102with the exception that the second adjuster block 104 does not include athreaded bore. Rather, the second adjuster block 104 may include arecess 126 formed in an opposite side thereof as compared to the firstadjuster block 102. The recess 126 allows the second adjuster block 104to engage a portion of the illumination assembly 16 such that at least aportion of the illumination assembly 16 is disposed between the firstand second adjuster blocks 102, 104, as shown in FIG. 5.

The biasing member 106 may be positioned generally between an inner wallof the main body 26 and the second adjuster block 104 and may cause thesecond adjuster block 104 to be biased toward the side surface 36 of themain body 26. As with the height-adjustment mechanism 72, imparting abias on the adjuster blocks 102, 104 and, thus, the adjustment screw100, prevents inadvertent rotation of the adjustment screw 100 relativeto the housing 12. Preventing inadvertent rotation of the adjustmentscrew 100 relative to the housing 12 prevents unwanted movement of thereticle 22 relative to the optical element 18 and ensures that the setposition of the adjustment screw 100 relative to the housing 12 ismaintained. While the biasing member 106 is shown as being a coilspring, any biasing member that imparts a force on the adjuster blocks102, 104 to urge the adjuster blocks generally toward the side surface36 such as, for example, a linear spring, may be employed.

The graduations 40 that are permanently affixed to or formed in the sidesurface 36 of the housing 12 help facilitate adjustment of theadjustment screw 100 relative to the housing 12 and allow a user tovisually observe the position of the adjustment screw 100 relative tothe housing 12. As with the graduations 38, the graduations may bepainted on and/or laser etched into the housing 12 such that thegraduations 40 are permanently fixed relative to the housing 12.Furthermore, each graduation 40 may be positioned relative to eachdetent 101 such that each audible noise or “click” corresponds tomovement of the screw 100 one graduation 40.

While the second adjuster block 104 may be a solid block such that thebiasing member 106 engages an outer surface thereof to urge the secondadjuster block toward the side surface 36, the second adjuster block 104could alternatively include a bore 128 partially formed therethrough.The bore 128 may receive at least a portion of the biasing member 106therein such that the biasing member 106 imparts a force on an endsurface generally within the bore 128. Providing the second adjusterblock 104 with an internal bore 128 reduces the weight of the secondadjuster block 104 and, as such, reduces the overall weight of theoptical sight 10.

With particular reference to FIGS. 3 and 5, the illumination assembly 16is shown and may include a circuit board 130, an LED 132, a photodetector 134, and a power source 136. The circuit board 130 may besupported by a substrate 138 generally within the housing 12, which mayinclude a slot 140 that slidably receives the projection 98 of theadjuster block 78. As described above, the adjuster block 78 may bemoved up/down when the adjustment screw 76 is rotated relative to thehousing 12. Because the projection 98 is received within the slot 140 ofthe substrate 138, up or down movement of the adjuster block 78 relativeto the housing 12 causes concurrent up or down movement of the substrate138 relative to the housing 12.

The projection 98 may be slidably received within the slot 140 to permitthe substrate 138 to slide relative to the projection 98 when the firstand second adjuster blocks 102, 104 are moved in the left/rightdirections relative to the housing 12. Furthermore, the substrate 138may include a width substantially equal to a width of the recesses 124,126 of the first and second adjuster blocks 102, 104 to allow thesubstrate 138 to be matingly received within the respective recesses124, 126. Positioning the substrate 138 within each of the recesses 124,126 of the respective adjuster blocks 102, 104 allows the substrate 138to be moved along with the first and second adjuster blocks 102, 104when the adjuster blocks 102, 104 are moved relative to the housing 12.

The circuit board 130 may be fixedly attached to the substrate 138 viaepoxy or the like. As such, the circuit board 130 may be fixed formovement with the substrate 138 such that when the substrate 138 ismoved by either the adjuster block 78 or the first and second adjusterblocks 102, 104, the circuit board 130 is moved therewith. The circuitboard 130 may support the LED 132 and photo detector 134 such thatmovement of the circuit board 130 relative to the housing 12 causesconcurrent movement of the LED 132 and photo detector 134 relative tothe housing 12. In one configuration, the LED 132 and photo detector 134are encapsulated on the circuit board 130 using a transparent epoxy orother coating. In another configuration, the LED 132 may be disposedproximate to the circuit board 130 and may be attached thereto while thephoto detector 134 is disposed adjacent to the optical element 18 (FIG.3). Positioning the photo detector 134 proximate to the optical element18 allows light to be collected from multiple angles and be transmittedto the photo detector 134 via the optical element 18.

Regardless of the particular location of the photo detector 134, the LED132 and photo detector 134 may be selectively controlled by the circuitboard 130, whereby the photo detector 134 selectively causes the LED 132to illuminate in response to ambient light conditions. Illumination ofthe LED 132 causes the LED 132 to direct light generally toward theoptical element 18 to display the reticle 22 on the optical element 18.

The power source 136 may be in electrical communication with at leastone of the circuit board 130, LED 132, and photo detector 134 via acontact strip 142. In one configuration, the power source 136 may be abattery having a generally circular shape. The battery may be receivedwithin a recess 144 of the housing 12 and may be held within the recess144 by a magnet 146, which allows for removal and replacement of thebattery when the battery requires replacement.

As described above, the circuit board 130, the LED 132, the photodetector 134, and the substrate 138 are disposed generally within thehousing 12. The circuit board 130, LED 132, photo detector 134, andsubstrate 138 are protected from environmental conditions by a sightglass 148 that may be disposed generally between the LED 132 and theoptical element 18. The sight glass 148 may be sealed against thehousing 12 by an epoxy or other suitable adhesive. Positioning epoxybetween the sight glass 148 and the housing 12 prevents debris fromentering the housing 12 and contacting components of the illuminationassembly 16 and adjustment assembly 14.

The housing 12 may include a projection 150 that extends generally overan edge of the sight glass to restrict water and other debris fromcontacting on an outer surface of the sight glass 148. Preventing waterand other debris from contacting an outer surface of the sight glass 148ensures that light from the LED 132 is not diverted or blocked andtherefore reaches the optical element 18. Because the optical sight 10may be used on a firearm 20 by law enforcement and/or militarypersonnel, the optical sight 10 may be subjected to extreme weatherconditions such as, for example, rain, wind, and ice. Providing thehousing 12 with the projection 150 helps prevent such weather conditionsfrom reaching the sight glass 148 and therefore improves the ability ofthe LED 132 in consistently providing light to the optical element 18and displaying the reticle 22 thereon.

In addition to preventing intrusion of debris and/or fluid into thehousing 12 at the sight glass 148, the illumination assembly 16 may befurther protected from intrusion of such debris and/or fluid byproviding an O-ring seal 152, a sticker 154, and a bottom cover orsticker 156. The stickers 154, 156 may be placed on a bottom portion ofthe housing 12 to seal components of the adjustment assembly 14 and/orillumination assembly 16 within the housing 12. The stickers 154,156 maybe formed of a material that prevents a user from tampering with thecomponents of the adjustment assembly 14 and/or illumination assembly 16by forming the stickers 154, 156 of a material that tears if tamperedwith.

The O-ring seal 152 may be received within a recess 158 (FIG. 3), whichmay surround an outer perimeter of a bottom portion of the housing 12.The O-ring seal 152 may engage an outer structure such as, for example,a base or mount 160, as shown in FIG. 15. The base 160 may include agenerally flat upper surface 162, at least one projection 164, and atleast one threaded aperture 166. In one configuration, the base 160 mayinclude two projections 164 that are spaced to accommodate the O-ringseal 152. The projections 164 reduce the overall cost and complexity ofmanufacturing the base 160 and housing 12 when compared to mountsincorporating four or more projections.

The O-ring seal 152 may engage the upper surface 162 of the base 160when the housing 12 is installed on the base 160. Prior to installationof the housing 12 on the base 160, the battery cover 154 may be placedgenerally over the power source 136 while the bottom cover 156 may begenerally placed over a portion of the housing 12 proximate to theadjustment assembly 14 and illumination assembly 16. Once the O-ringseal 152, battery cover 154, and bottom cover 156 are installed on thehousing 12, the housing 12 may be installed on the base 160.

The base 160 may include a lower surface 168 having a generally arcuateshape to accommodate an arcuate shape of a gun barrel 24.

In another configuration, the bottom surface 168 of the base 160 mayinclude a generally flat or planar surface to accommodate a barrelhaving a generally flat or planar top surface. In either configuration,the base 160 may be secured to the firearm 20 via at least one fastener(not shown). The housing 12 may be attached to the base 160 via thefasteners 48, which may be threadably received within the threadedapertures 166 of the base 160. In addition, the housing may include apair of openings (not shown) that matingly engage the projections orposts 164 of the base 160 to prevent rotation or other movement of thehousing 12 relative to the base 160 once the housing 12 is installed onthe base 160.

With particular reference to FIGS. 3-5, the optical element 18 is shownto include a doublet lens having a first lens 170, a second lens 172,and a dichroic coating formed on at least one of the first and secondlenses 170, 172 to allow light from the LED 132 to be reflected thereon.Coating one of the lenses 170, 172 with the dichroic coating 174 allowsthe LED 132 to generate the reticle 22 in an area generally between thelenses 170, 172 and therefore allows the reticle 22 to be displayed onthe optical element 18. The lenses 170, 172 may include a substantiallyD-shape and may include an upper surface 176 having a generally convexshape. Once the optical element 18 is installed in the housing 12, theupper surface 176 of the optical element 18 may be positioned generallyadjacent to the bottom surface 68 of the cross member 66.

The lenses 170, 172 may be spherical lenses, whereby at least one of thelenses 170, 172 includes a diameter substantially equal to 33.5millimeters. Once the spherical lenses 170, 172 are formed, an overallheight of the lenses 170, 172 may be substantially equal to 16.34millimeters. Regardless of the exact size of the lenses 170, 172, theoptical element 18 may include an effective focal length of 26.55millimeters and may be formed from SCHOTT S-3 Grade A fine annealedmaterial.

With particular reference to FIGS. 1-5, operation of the optical sight10 will be described in detail. When the optical sight 10 is initiallyinstalled on the firearm 20, a flathead screwdriver, hexagonalscrewdriver, or any generally flat member may be inserted into thehexagonal configuration 56 and/or longitudinal slot 58 to rotate thefasteners 48 relative to the housing 12. Sufficient rotation of thefasteners 48 relative to the housing 12 causes the threaded shank 50 ofeach fastener 48 to engage a respective threaded aperture 166 of thebase 160. Once the fasteners 48 are sufficiently rotated relative to thehousing 12, the head portion 52 of each fastener 48 generally engagesthe housing 12 at the taper 54 and secures the housing 12 to the base160.

Once the housing 12 is secured to the base 160, adjustment of theposition of the reticle 22 within the optical element 18 may beperformed. Specifically, a flat tool such as, for example, a screwdriveror spent casing, may be inserted into the slot 88 of the adjustmentscrew 76 to rotate the adjustment screw 76 relative to the housing 12.As described above, rotation of the adjustment screw 76 relative to thehousing 12 causes up/down movement of the adjuster block 78 relative tothe housing 12. Movement of the adjuster block 78 in the up directionmay be accomplished by rotation of the adjustment screw 76 in aclockwise direction, as shown in FIG. 5. If movement of the adjustmentscrew 76 in the clockwise direction causes upward movement of theadjuster block 78, counterclockwise rotation of the adjustment screw 76would cause downward movement of the adjuster block 78 relative to thehousing 12.

Because the projection 98 of the adjuster block 78 is slidably receivedwithin the slot 140 of the substrate 138, up/down movement of theadjuster block 78 relative to the housing 12 causes likewise movement ofthe substrate 138 relative to the housing 12. Moving the substrate 138relative to the housing 12 causes concurrent movement of the circuitboard 130, LED 132, and photo detector 134 relative to the housing 12.By moving the LED 132 with the substrate 138 and adjuster block 78,movement of the light transmitted by the LED 132 is similarly adjusted.Because this light generates the reticle 22 on the optical element 18,up/down movement of the LED 132 relative to the housing 12 causesconcurrent up/down movement of the reticle 22 relative to the opticalelement 18. Once the user properly aligns the reticle 22 in the up/downposition relative to the optical element 18, the flathead screwdriver orspent casing may be removed from the slot 88 of the adjustment screw 76.The adjustment screw 76 will be maintained in the set position based onengagement of the biasing member 80 with the adjuster block 78 andhousing 12.

Once the up/down adjustment of the reticle 22 is accomplished, theflathead screwdriver or spent casing may be inserted into the slot 114of the adjustment screw 100. Rotation of the adjustment screw 100 by theflathead screwdriver or spent casing causes the first and secondadjuster blocks 102, 104 to move relative to the housing 12. Asdescribed above, movement of the adjuster blocks 102, 104 relative tothe housing 12 causes concurrent movement of the substrate 138 relativeto the housing 12. Because the circuit board 130, LED 132, and photodetector 134 may be attached to the substrate 138, movement of thesubstrate 138 relative to the housing 12 causes concurrent movement ofthe circuit board 130, LED 132, and photo detector 134.

Moving the LED 132 relative to the housing 12 likewise causes movementof the light generated by the LED 132 to move relative to the housing12. Movement of the light from the LED 132 relative to the housing 12causes the light to move relative to the optical element 18 andtherefore adjusts the left/right position (i.e., the “windage”) of thereticle 22 relative to the optical element 18. For example, if theadjustment screw 100 is rotated in the counterclockwise direction andthe LED 132 is moved generally to the right rotation of the adjustmentscrew 100 in the clockwise direction will cause movement of the LED 132to the left.

Once the windage of the reticle 22 is adjusted, the flathead screwdriveror spent shell casing may be removed from the slot 114 of the adjustmentscrew 100. As described above, the biasing member 106 imparts a force onthe first and second adjuster blocks 102, 104 and substrate 138 andtherefore locks the position of the adjustment screw 100. As such, theset position of the adjustment screw 100 and, thus, the LED 132, ismaintained when the flathead screwdriver or spent shell casing isremoved from engagement with the adjustment screw 100. While adjustmentof the reticle 22 in the up/down direction is described as beingperformed prior to adjustment of the windage of the reticle 22,adjustment of the windage of the reticle 22 could be performed prior toor concurrently with adjustment of the up/down direction of the reticle22.

Once the position of the reticle 22 is adjusted relative to the opticalelement 18, the optical sight 10 may be used to properly align thebarrel 24 of the firearm 20 relative to a target (now shown). Inoperation, the photo detector 134 senses ambient light conditions andadjusts the amount of power supplied to the LED 132 from the powersource 136. For example, in bright conditions, the photo detector 134may supply the LED 132 with more power from the power source 136 toilluminate the reticle 22 at a higher intensity to allow the reticle 22to stand out under such high ambient light conditions. Conversely, whenambient light conditions are low, the photo detector 134 may supply theLED 132 with less power from the power source 136, as less illuminationof the reticle 22 is required to allow the reticle 22 to be seen.

In either of the foregoing conditions, the LED 132 supplies lightgenerally through the sight glass 148 and above the steps 44 of the mainbody 26 towards the optical element 18. Because the optical element 18includes a dichroic coating 174 disposed on at least one of the firstlens 170 and the second lens 172, the wave length of the light from theLED 132 is reflected and causes the reticle 22 to appear in the opticalelement 18 along the line-of-sight shown in FIG. 3. The reticle 22 maybe used by the user to align the barrel 24 of the firearm 20 with atarget.

With particular reference to FIGS. 6-10, an optical sight 10 a isprovided. In view of the substantial similarity in structure andfunction of the components associated with the optical sight 10 withrespect to the optical sight 10 a, like reference numerals are usedhereinafter and in the drawings to identify like components while likereference numerals containing letter extensions are used to identifythose components that have been modified.

As with the optical sight 10, the optical sight 10 a may include ahousing 12 a, an adjustment assembly 14 a, an illumination assembly 16a, and an optical element 18. The optical sight 10 a may be mounted to afirearm 20 via a base 160 through engagement of fasteners 48 withthreaded apertures 166 of the base 160.

The housing 12 a may include a main body 26 and an upwardly extendingportion 28 a. The upwardly extending portion 28 a may include a pair ofposts 62 a and a cross member 66 a. As with the optical sight 10 a, theposts 62 a extend generally from the main body 26 a greater distancethan the cross member 66 a. As such, the cross member 66 a may include agenerally concave shape, whereby a center portion of the cross member 66a extends below distal ends of each of the posts 62 a.

A channel 178 may extend from each post 62 a into the cross member 66 afor receiving at least a portion of the illumination assembly 16 a.Furthermore, each post 62 a may include an attachment aperture 180 forsecuring at least a portion of the illumination assembly 16 a to theupwardly extending portion 28 a of the housing 12 a.

The illumination assembly 16 a may be received at least partially withinthe channel 178 of the upwardly extending portion 28 a and may include afiber optic 182, a fiber optic sticker 184, and a fiber cover 186. Theillumination assembly 16 a may be of the type disclosed in assignee'scommonly owned U.S. Pat. No. 5,653,034, the disclosure of which isincorporated herein by reference.

The fiber optic 182, fiber optic sticker 184, and fiber cover 186 may beat least partially disposed within the channel 178. In anotherconfiguration, the fiber optic 182, fiber optic sticker 184, and fibercover 186 may be completely disposed within the channel 178 such that anouter surface of the fiber cover 186 is substantially flush with anouter surface of each post 62 a and a top portion of the cross member 66a. In another configuration, the fiber optic 182, fiber optic sticker184, and fiber cover 186 may protrude from an outer surface of both ofthe posts 62 a from a surface of the cross member 66 a to permit morelight to be gathered by the fiber optic 182.

As shown in FIG. 10, the fiber optic 182 is a substantially elongatefiber that may be wrapped multiple times and be positioned and shapedwithin the channel 178. The fiber optic 182 may extend from a bottomportion of one of the posts 62 a and into a recess 188. From the recess188, the fiber optic 182 may pass through a central portion of the mainbody 26 and be received proximate to a portion of the adjustmentassembly 14 a to allow light from the fiber optic 182 gathered at theposts 62 a and cross member 66 a to be displayed through the sight glass148 and onto the optical element 18 via a distal end 183 of the fiberoptic 182.

Once the fiber optic 182 is positioned properly relative to the upwardlyextending portion 28 a and recess 188, the fiber optic 182 may besecured to the housing 12 a by inserting a pair of fasteners 190 throughapertures 192 of the fiber cover 186 and through apertures 194 of thefiber optic sticker 184 to fix the fiber optic 182 relative to the posts62 a and cross member 66 a.

In addition to the fiber optic 182, fiber optic sticker 184, and fibercover 186, the illumination assembly 16 a may also include a tritiumlamp 196. The tritium lamp 196 may be disposed generally within therecess 188 of the housing 12 a and may be disposed proximate to or incontact with the fiber optic 182 disposed within the recess 188. Thetritium lamp 196 may cooperate with the fiber optic 182 to direct lightthrough the sight glass 148 and toward the optical element 18.

In addition to the tritium lamp 196, the illumination assembly 16 a mayalso include an LED (not shown) that can be used in conjunction with orin place of the fiber optic 182 and tritium lamp 196. For example, iflight from the fiber optic 182 and/or tritium lamp 196 is insufficient,the LED may be energized to illuminate the reticle 22. Generallyspeaking, the illumination assembly 16 a may illuminate the reticle 22via any combination of the fiber optic 182, tritium lamp 196, and LED.

The particular configuration of the chosen light source (i.e., fiberoptic 182, tritium lamp 196, and/or LED) may depend on ambient-lightconditions. For example, when ambient-light conditions are dark, the LEDmay be required to supplement the fiber optic 182 and/or tritium lamp196. Conversely, when ambient-light conditions are light, the LED andtritium lamp 196 may not be required, as sufficient light may becollected and transmitted via the fiber optic 182 alone.

A sticker 156 a may be placed on a bottom portion of the housing 12 a toseal components within the housing 12 a. The sticker 156 a may be formedof a material that prevents a user from tampering with the components ofthe adjustment assembly 14 a and/or illumination assembly 16 a byforming the sticker 156 a from a material that tears if tampered with.In addition, a lamp cover 157 may be positioned on a bottom portion ofthe housing 12 a to seal recess 188. The lamp cover 157 may be removablyattached to the housing 12 a via a suitable fastener 159.

With continued reference to FIGS. 8-10, the adjustment assembly 14 a isprovided and may include a height-adjustment mechanism 72 and awindage-adjustment mechanism 74 a. The windage-adjustment mechanism 74 amay include a first adjuster block 102 a and a second adjuster block104. As with the first and second adjuster blocks 102 a, 104 of theoptical sight 10 a, the first adjuster block 102 a and second adjusterblock 104 may be in contact with the illumination assembly 16 a toselectively adjust a left/right position of light supplied to theoptical element 18 by the illumination assembly 16 a.

The first adjuster block 102 a may include a recess 124 a having adifferent shape than the recess 124 of the first adjuster block 102 thataccommodates a substrate 138 a of the illumination assembly 16 a.Specifically, the recess 124 a of the first adjuster block 102 a mayinclude a shape that matingly engages the substrate 138 a to allow thesubstrate 138 a to be moved concurrently with the first adjuster block102 a.

The substrate 138 a may include an extension 198 and an aperture 200,whereby the extension 198 is received generally within the recess 124 aof the first adjuster block 102 a. The aperture 200 may be formedthrough the substrate 138 a and may receive a distal end 183 of thefiber optic 182.

With continued reference to FIGS. 8-10, operation of the optical sight10 a will be described in detail. Once the optical sight 10 a is mountedto the base 160 via fasteners 48, the optical sight 10 a may be adjustedto properly align the position of the reticle 22 relative to the barrel24 of the firearm 20. A flathead screwdriver or other generally flatmember may be inserted into the slot 88 of the adjustment screw 76 torotate the adjustment screw 76 relative to the housing 12 a. Rotation ofthe adjustment screw 76 relative to the housing 12 a causes concurrentup/down movement of the adjuster block 78 relative to the housing 12 a.Because the projection 98 of the adjuster block 78 is slidably receivedwithin a slot 140 a of the substrate 138 a, the substrate 138 a iscaused to move concurrently in the up or down direction with theadjuster block 78.

Movement of the substrate 138 a in either the up or down directioncauses concurrent movement of the aperture 200 in the up or downdirection. Because the distal end 183 of the fiber optic 182 is receivedwithin the aperture 200, the distal end 183 of the fiber optic 182 issimilarly caused to move in either the up or down direction. The distalend 183 of the fiber optic 182 outputs light collected by the fiberoptic 182 at the posts 62 a, at the cross member 66 a, or from thetritium lamp 196 generally through the sight glass 148 and toward theoptical element 18 to generate the reticle 22 on the optical element 18.Therefore, up or down movement of the substrate 138 a and distal end 183of the fiber optic 182 causes concurrent up or down movement of thereticle 22 on the optical element 18.

Once the position of the reticle 22 is adjusted in the up/downdirection, the flathead screwdriver or flat tool may be removed fromengagement with the adjustment screw 76. As with the height-adjustmentmechanism 72 of the optical sight 10, the up/down position of thereticle 22 relative to the optical element 18 is maintained due to theforce imparted on the adjuster block 78 by biasing members 80, 91.Specifically, biasing member 80 applies a force on the adjuster block 78between the substrate 138 a and the adjuster block 78 while biasingmember 91 applies a force directly on substrate 138 a, which in turnapplies a force on the adjuster block 78 due to engagement betweenprojection 98 of the adjuster block 78 and slot 140 a of the substrate138 a.

The left/right (i.e., windage) of the reticle 22 may be adjusted byinserting a flathead screwdriver or other flat object into the slot 114of the adjustment screw 100. Once the flathead screwdriver or other flatmember is inserted into the slot 114 of the adjustment screw 100,rotation of the adjustment screw 100 relative to the housing 12 a causesconcurrent movement of the first and second adjuster blocks 102 a, 104.Movement of the adjuster blocks 102 a, 104 causes concurrent movement ofthe substrate 138 a relative to the housing 12 a in a direction towardand away from the side surface 36 of the main body 26. Because thesubstrate 138 a supports the distal end 183 of the fiber optic 182,movement of the substrate 138 a in either the left or right directionrelative to the housing 12 a similarly causes movement of the distal end183 of the fiber optic 182 relative to the housing 12 a. As describedabove, movement of the distal end 183 of the fiber optic 182 relative tothe housing 12 a causes concurrent movement of the reticle 22 relativeto the optical element 18. Once the position of the reticle 22 relativeto the optical element 18 is adjusted, the flathead screwdriver or flattool may be removed from engagement with the adjustment screw 100. Aswith the windage-adjustment mechanism 74 of the optical sight 10, theset position of the windage is maintained due to the force imparted onthe first and second adjuster blocks 102 a, 104 by the biasing member106.

Once the up/down position and windage position of the reticle 22 isproperly adjusted relative to the optical element 18, the optical sight10 may be used to align the barrel 24 of the firearm 20 relative to atarget (not shown).

The reticle 22 may be illuminated by a combination of the fiber optic182 and the tritium lamp 196 or may be illuminated solely by the fiberoptic 182 or solely by the tritium lamp 196. For example, in highambient light conditions, sufficient light may be captured by the fiberoptic 182 and directed through the distal end 183 of the fiber optic 182toward the optical element 18 such that the tritium lamp 196 is not usedat all or is only partially used. Under dark conditions where ambientlight is low, the fiber optic 182 may not be able to capture enoughlight to supply the distal end 183 of the fiber optic 182 withsufficient light to illuminate the reticle 22 on the optical element 18.Under such dark conditions, the tritium lamp 196 may be used inconjunction with the fiber optic 182 to sufficiently illuminate thereticle 22. Under certain circumstances, if the firearm 20 is used intotal darkness, the tritium lamp 196 may be exclusively used, wherebylight is not captured by the fiber optic 182. Rather, light emanatingfrom the distal end 183 of the fiber optic 182 is generated solely bythe tritium lamp 196. Under most conditions, however, light supplied atthe distal end 183 of the fiber optic 182 will come from a combinationof light gathered by the fiber optic 182 and received from the tritiumlamp 196.

Because the optical element 18 includes a dichroic coating 174 disposedon at least one of the first lens 170 and the second lens 172, the wavelength of the light from the fiber optic 182 and/or tritium lamp 196 isreflected and causes the reticle 22 to appear in the optical element 18along the line-of-sight shown in FIG. 8. The reticle 22 may be used bythe user to align the barrel 24 of the firearm 20 with a target.

With particular reference to FIG. 11, an optical sight 10 b is provided.In view of the substantial similarity in structure and function of thecomponents associated with the optical sight 10 with respect to theoptical sight 10 b, like reference numerals are used hereinafter and inthe drawings to identify like components while like reference numeralscontaining letter extensions are used to identify those components thathave been modified.

As with the optical sight 10, the optical sight 10 b may include ahousing 12, an adjustment assembly 14, an illumination assembly 16 b,and an optical element 18. The optical sight 10 b may be mounted to afirearm 20 via a base 160 through engagement of fasteners 48 withthreaded apertures 166 of the base 160.

The illumination assembly 16 b may include a flexible circuit board 130b, an LED 132, a photo detector 134, and a power source 136. Theflexible circuit board 130 b may extend generally under the opticalelement 18 and may include a first actuation member 131 and a secondactuation member 133. Each actuation member 131, 133 may be used tocontrol illumination of the LED 132 and photo detector 134 and each maybe associated with a cover 135, 137.

In one configuration, the first and second actuation members 131, 133may be button switches in contact with respective covers 135, 137. Thecovers 135, 137 may be formed from a flexible material such as rubber orplastic such that when a force is applied to either cover 135, 137, therespective cover 135, 137 deflects and transmits the applied force tothe associated actuation member 131, 133. When either cover 135, 137 isdepressed, the actuation member 131, 133 associated with the particularcover 135, 137 is actuated to control operation of the LED and/or photodetector 134. Such control may be facilitated by providing descriptivemarkings on at least one of the covers 135, 137. For example, providingone actuation member 131 with a positive sign (+) and providing theother actuation member 133 with a negative sign (−) provides the userwith a quick reference as to which cover 135, 137 and associatedactuation member 131, 133 increases (+) or decreases (−) illumination.

As with the illumination assembly 16, the illumination assembly 16 b maysimilarly be protected from debris and/or fluid by providing an O-ringseal 152, a sticker 154, and a bottom cover or sticker 156. The stickers154, 156 may be placed on a bottom portion of the housing 12 to sealcomponents of the adjustment assembly 14 and/or illumination assembly 16a within the housing 12.

The illumination assembly 16 b may also include at least one plug 161that is inserted into a slot 163 formed through the housing 12 in anarea proximate to each actuation member 131, 133. The slot 163 allowseach actuation member 131, 133 to extend through the housing 12 and bepositioned proximate to a cover 135, 137. The plug 161 maintains thesealed nature of the housing 12 to prevent intrusion of water and otherdebris from entering the housing 12 and contacting the adjustmentassembly 14 and/or illumination assembly 16 b.

One end of the circuit board 130 b may be fixedly attached to thesubstrate 138 via epoxy or the like. As such, the circuit board 130 maybe fixed for movement with the substrate 138 such that when thesubstrate 138 is moved by either the adjuster block 78 or the first andsecond adjuster blocks 102, 104, the circuit board 130 b is movedtherewith. The circuit board 130 b may support the LED 132 and photodetector 134 such that movement of the circuit board 130 b relative tothe housing 12 causes concurrent movement of the LED 132 and photodetector 134 relative to the housing 12. In one configuration, the LED132 and photo detector 134 are encapsulated on the circuit board 130 bproximate to the substrate 138 using a transparent epoxy or othercoating. In another configuration, the LED 132 may be disposed on thecircuit board 130 b and may be attached thereto proximate to thesubstrate 138 while the photo detector 134 is disposed adjacent to theoptical element 18.

While the photo detector 134 is described as being positioned proximateto either the substrate 138 or the optical element 18, the photodetector 134 could be positioned anywhere on the circuit board 130 b aslong as the photo detector 134 is exposed to ambient light.

Regardless of the particular location of the photo detector 134, the LED132 and photo detector 134 may be selectively controlled by the circuitboard 130 b, whereby the photo detector 134 selectively causes the LED132 to illuminate in response to ambient-light conditions. Illuminationof the LED 132 causes the LED 132 to direct light generally toward theoptical element 18 to display the reticle 22 on the optical element 18.

The flexible circuit board 130 b may be configured such that theillumination assembly 16 b may operate in either an automatic mode or amanual mode. For example, when the illumination assembly 16 b isinitially activated by depressing either cover 135, 137, theillumination assembly 16 b may default to the automatic mode. In theautomatic mode, the intensity of the LED 132 is controlled based onambient-light conditions, as detected by the photo detector 134.

The automatic mode may be overridden by depressing either cover 135, 137such that one of the actuation members 131, 133 is actuated. Depressingeither cover 135, 137 during the automatic mode may cause theillumination assembly 16 b to enter the manual mode, whereby theintensity of the LED 132 is controlled based on manual input to eitheror both of the actuation members 131, 133 of the circuit board 130 b viadepression of covers 135, 137. During the manual mode, light intensityis not controlled based on ambient-light conditions and is notcontrolled based on information received from the photo sensor 134. Forexample, depression of cover 137 and associated actuation member 131causes the intensity of the LED 132 to be reduced. Similarly, depressionof cover 135 and associated actuation member 133 causes the intensity ofthe LED 132 to be increased.

The circuit board 130 b may also be configured such that when the covers135, 137 are simultaneously depressed for a first predetermined timeperiod the illumination assembly 16 b returns to the automatic mode andwhen depressed for a second predetermined time period turns off. In oneconfiguration, the first predetermined time period is any time less thanapproximately three (3) seconds while the second predetermined timeperiod is approximately equal to three (3) seconds or more.

With particular reference to FIGS. 12A-12D, 13, and 14, variations ofthe illumination assembly 16 a are provided. FIG. 12A shows a beamsplitter 202, which includes a coating 204 disposed generally betweenfirst and second halves 206, 208 of the beam splitter 202, whereby thebeam splitter halves 206, 208 are right-angled prisms. The beam splitter202 may be of the type disclose in assignee's commonly owned U.S. Pat.No. 6,807,742, the disclosure of which is incorporated herein byreference.

The coating 204 may include an opening 210 defining the shape of thereticle 22 (see FIG. 12B). In another configuration, the coating may beon surfaces 212 and 216 (see FIG. 12C) and in yet another configuration,the coating may be on surface 214 (see FIG. 12D). In either of theforegoing configurations, the reticle 22 may include any shape. If thecoating including the opening defining the reticle 22 is on a pair ofsurfaces such as, for example, surfaces 212 and 216, the coating (204;i.e., mask) must be applied such that the opening for defining thereticle 22 is exactly aligned to ensure that the reticle 22 is clearlyshown on the optical element 18.

FIG. 12A provides an example, whereby light from SOURCE 1 220 iscombined with light from SOURCE 2 218, whereby SOURCE 1 220 is one of afiber optic, an LED, and a tritium lamp and SOURCE 2 218 is one of afiber optic, an LED, and a tritium lamp. As shown in FIG. 12A, lightfrom SOURCE 2 218 may be completely transmitted while light from SOURCE1 220 may be completely reflected. Alternatively, any combination oflight between thirty (30) percent and seventy (70) percent of eachsource 218, 220 may be used provided the combination equalssubstantially one-hundred (100) percent. In the foregoing configurationshown in FIG. 12A, the beam splitter 202 may be positioned proximate tothe sight glass 148 such that light from the beam splitter 202 isreceived by the optical element 18.

With particular reference to FIGS. 13 and 14, a switch 222 is providedand may receive an input from more than one source (i.e., from an LED226 and a fiber 224). The switch 222 may include a movable body 228having an output fiber 230 fixed for movement therewith, whereby lightfrom the LED 226 and light from the fiber 224 may be selectivelysupplied to the output fiber 230. Specifically, the output fiber 230 maybe moved through movement of the body 228 between connection with thefiber 224 and a fiber 234 attached to the LED 226. Therefore, by movingthe body 228 relative to a housing 232 supporting the body 228, theoutput fiber 230 may be selectively supplied with light either from theLED 226 via conduit 234 or with light from the fiber 224 and cantherefore supply the output fiber 230 with light from one of two sourcesindependent from one another. An end of the output fiber 230 may bereceived generally within a substrate such as the substrate 138 a ofFIG. 10. As such, the output from output fiber 230 may be directed tothe optical element 18 to supply the optical element 18 with the reticle22.

While the switch 222 is shown as including a slidable body 228, theswitch 222 could alternatively include a rotatable member (not shown)that allows a user to select between a mode, whereby the LED 226 isexclusively used or a mode whereby the fiber 224 is exclusively used.

In either of the foregoing configurations, a tritium lamp 225 may beused in conjunction with the fiber 224 and/or LED 226 to enhance theability of the fiber 224 and/or LED 226 to supply light to the outputfiber 230. The tritium lamp 225 could alternatively supply light to theoutput fiber 230 independent of the fiber 224 and/or LED 226 such thatthe switch 222 supplies light to the output fiber 230 from any one ofthe fiber 224, the LED 226, or the tritium lamp 225 individually byselectively moving the slidable body 228 relative to the respectivesources 224, 226, 225. While the tritium lamp 225 may be used incombination with the fiber 224 and/or LED 226, any of the sources 224,226, 225 could be combined by the switch 222 to provide light frommultiple sources simultaneously.

1. An optical sight comprising: a housing; an optical element supportedby said housing; a reticle; and an illumination system selectivelydisplaying said reticle on said optical element and including a switchsupplying said optical element with light from one of a first lightsource and a second light source to generate said reticle.
 2. Theoptical sight of claim 1, wherein said switch includes a first inputmember associated with said first light source, a second input memberassociated with said second light source, and an output member supplyinglight from one of said first light source and said second light sourceto generate said reticle.
 3. The optical sight of claim 2, wherein saidswitch includes a movable body movable between said first input memberand said second input member to place one of said first input member andsaid second input member in communication with said output member. 4.The optical sight of claim 3, wherein said output member is movable withsaid movable body relative to said first input member and said secondinput member.
 5. The optical sight of claim 3, wherein said outputmember extends through said movable body.
 6. The optical sight of claim2, wherein at least one of said first input member, said second inputmember, and said output member are an optical fiber.
 7. The opticalsight of claim 1, wherein said first light source is one of an LED andan optical fiber and said second light source is the other of said LEDand said optical fiber.
 8. The optical sight of claim 7, furthercomprising a tritium lamp in communication with said optical fiber. 9.The optical sight of claim 1, further comprising a third light source,said switch supplying said optical element with light from one of saidfirst light source, said second light source, or said third light sourceto generate said reticle.
 10. The optical sight of claim 1, wherein atleast one of said first light source and said second light sourceincludes multiple light sources.
 11. The optical sight of claim 10,wherein said multiple light sources include at least one of a fiberoptic, an LED, or a tritium lamp.
 12. The optical sight of claim 1,wherein said first light source is at least one of a fiber optic, anLED, and a tritium lamp and said second light source is at least one ofa fiber optic, an LED, and a tritium lamp.
 13. An optical sightcomprising: a housing; an optical element supported by said housing; areticle; and an illumination system selectively displaying said reticleon said optical element and including a beam splitter combining lightfrom a first light source and a second light source to generate saidreticle, said beam splitter including a mask formed on a surface of saidbeam splitter and defining a shape of said reticle.
 14. The opticalsight of claim 13, wherein said beam splitter includes a pair ofright-angled prisms.
 15. The optical sight of claim 14, wherein saidmask is applied to at surface of one of said right-angled prisms at ajoint between said pair of right-angled prisms.
 16. The optical sight ofclaim 14, wherein said mask is applied to a surface of at least one ofsaid right-angled prisms, said surface being spaced apart from a jointbetween said pair of right-angled prisms.
 17. The optical sight of claim14, wherein said mask is applied to a first surface of one of said pairof right-angled prisms and is applied to a second surface of the otherof said pair of right-angled prisms.
 18. The optical sight of claim 17,wherein said first surface is positioned approximately ninety (90)degrees from said second surface.
 19. The optical sight of claim 13,wherein said first light source includes at least one of an LED, anoptical fiber, and a tritium lamp and said second light source includesat least one of an LED, an optical fiber, and a tritium lamp.
 20. Theoptical sight of claim 19, wherein said beam splitter joinsapproximately thirty (30) percent of light from one of said LED and saidoptical fiber and approximately seventy (70) percent of light from theother of said LED and said optical fiber to generate said reticle onsaid optical element.
 21. An optical sight comprising: a housing; anoptical element supported by said housing; a reticle; and anillumination system including a light source for selectively displayingsaid reticle on said optical element and a photo detector operable todetect ambient light conditions, said photo detector exposed to ambientlight conditions via said optical element.
 22. The optical sight ofclaim 21, wherein said photo detector is disposed adjacent to saidoptical element.
 23. The optical sight of claim 21, wherein said photodetector is disposed between said housing and said optical element. 24.The optical sight of claim 21, wherein said light source is an LED. 25.The optical sight of claim 21, wherein said illumination system includesa controller operable to adjust an intensity of said light source inresponse to information received from said photo detector.